This disclosure relates to a fluid coupling such as for use during the transfer or bulk delivery of a cryogenically controlled liquid, such as carbon dioxide, and to methods of connection to form the coupling and disconnecting of the coupling.
By way of example, the beverage industry uses carbon dioxide (CO2) for carbonation, and for purposes of re-supplying carbon dioxide to a large consumer, such as a restaurant, service center, or like facility, carbon dioxide is typically transported in a cryogenically controlled liquid form in a relatively large CO2 supply tank on a delivery truck. The restaurant or like business may have a free-standing CO2 tank located exterior of the building or may have a fill line permanently plumbed to the exterior wall of the building or like facility. For purposes of beginning a fill process, the truck operator connects a supply hose having a coupler to a fitting or nipple on an exterior tank or fill line of the facility, which may be within a lock box or the like, to thereby connect the supply tank to the fitting and enable bulk fluid delivery of carbon dioxide in liquid form to the consumer. Following the fill process, the coupler is disconnected from the nipple.
Cryogenically controlled liquids, such as carbon dioxide, need to be handled with care upon transferring from the supply tank to the receiving facility. In particular, the processes of connecting and disconnecting the coupler to and from the nipple can cause problems, and safe and reliable connection and disconnection are difficult due to the extremely low temperature and high pressure of the cryogenically controlled liquid to be transferred.
By way of example, while mechanical threaded connections have conventionally been used for providing such couplings or connections, various problems are encountered during connection and disconnection operations due to the low temperature, high pressure, and like characteristics of the cryogenically controlled liquid being delivered. For instance, couplings, surrounding support structures, containment boxes, and like components are often subject to damage while they become beaten as the coupler is being engaged to the nipple during connection and released from the nipple during disconnection. For instance, a rear sleeve clip or other like component can become loose on the coupler resulting in a free connection that creates a dangerous condition for the operator, especially if the coupler valve stays or sticks in an open condition thereby resulting in a hose-whip or kick-back condition.
In addition, coupler valves have a tendency to remain open after disconnection due to freezing and stiction issues, and operators are typically exposed to excessively high levels of CO2 during connection/disconnection processes. Further, seals and related components used to form seals within couplings can frequently and easily become damaged in the process.
Accordingly, couplings for CO2 and like cryogenically controlled liquid delivery systems have been problematic and unsafe. The problems encountered typically extend loading and unloading times, increase costs, and produce frequent product failures.
Although problems specifically with the bulk delivery of CO2 in the beverage industry are referenced above, these same problems can also relate to the loading, unloading, or transfer of any cryogenically controlled liquid in any industry.